AR 4 A great and sturdy pillow for the bottom’s comfort. I bought this to use as my bottom got sore from sitting for over six hours a day. The only problems I encountered with this cushion are as follows: It was a little big for some seats (the pillow would spill out over the edge of the seat, thus reducing comfort. This is a problem with the seats, and not the cushion). The other small problem is carrying the cushion around (it would be nice to have a nice cloth carry bag, that you can sit on, to hide the cushion from people on the train).